In IE under Tools-> Internet Options -> Programs there\'s a checkbox labelled \"Tell me if Internet Explorer is not the default web browser.\" What\'s the registry key that
For those trying to defeat corporate group policy, this does the trick in one command
reg add "HKCU\Software\Microsoft\Internet Explorer\Main" /f /v "Check_Associations" /d "no" /t REG_SZ
It's been answered in various ways over the web and here; here's one question which covers it; Windows RegKey - Default Browser Application Path. Then it's just checking if the path is the iexplore.exe path.
Update: I just checked what the key is that is modified when you deselect and reselect the "check default browser" option.
When you deselect it, the value
HKCU\Software\Microsoft\Internet Explorer\Main\Check_Associations is created, a REG_SZ containing the string "no".
When you reselect it, HKCU\Software\Microsoft\Internet Explorer\Main\Check_Associations is altered to "yes".
So: if HKCU\Software\Microsoft\Internet Explorer\Main\Check_Associations does not exist or is "yes", it will check. To avoid that check (potentially user-unfriendly behaviour - use with care - create as "no" or set to "no" the value HKCU\Software\Microsoft\Internet Explorer\Main\Check_Associations.
There are two keys:
HKEY_LOCAL_MACHINE\SOFTWARE\Classes\.htmHKEY_LOCAL_MACHINE\SOFTWARE\Classes\.htmlChange the Default Key value to: htmlfile or ChromeHTML
Not sure about Firefox, but if you set it here, you will not be asked.